The present invention relates to safety equipment for use in performing operations involving wheel and pressurized tire assemblies and, more particularly, to a safety barrier and restraint system that secures a wheel and pressurized tire assembly during service or installation operations and that forms a safety barrier and restraint mechanism.
Conventional tire changing apparatus generally comprise a flat surface for laying a wheel and tire assembly on its side so that tire removal, exchange and repair operations can be performed. In tire service or changing operations performed on conventional tire changers there exists the danger of unexpected rapid movement of the assembly or some of its components due to rapid release of tire pressure or explosion. This can be attributable to, for example, a faulty bead or rim, over-inflation or a damaged tire. Such rapid displacement of components may cause injury to an operator or damage to the surrounding environment, including the tire changing apparatus itself.
Some conventional tire changing apparatus are provided with or can be retrofitted with safety belts or brackets to restrain such movement of the wheel and tire assembly to prevent injurious contact with an operator or damage to the surrounding environment. Examples of known safety and restraint devices are described in U.S. Pat. Nos. 4,742,859; 4,865,104; 4,811,774; and 4,765,387, which are incorporated herein by reference. The devices described in these patents include an axially-mounted plunger-type arm having a foot that engages the top center of a wheel rim, a flat bracket that translates vertically along a post and can be positioned above a wheel assembly, a tubular bracket that swivels into place above a wheel assembly, and a flexible belt having a buckle that straps a wheel assembly to the flat tire-supporting surface. These patents also include known means for prohibiting inflation operations by preventing the release of pressurized air from an air source until the safety device is properly positioned or engaged. One of the known means includes a shortened air hose operatively attached to a safety bracket such that the hose will not reach a nozzle on a tire positioned in the apparatus unless the safety device is properly positioned. These and other known devices fail to provide a desired level of safety in tests performed by the present inventor due to limitations that are addressed and overcome by the present invention. For example, the known safety devices generally do not provide restraint against lateral movement of the wheel assembly or one of its components. Others do not provide strong enough barriers. Still, others do not provide means for positively locking or securing the safety device in the safety engaged position. All of the known systems require handling of substantially cumbersome equipment, additional time to operate, or an excessive amount of work area to manipulate all of the structural components. These and other shortcomings of known systems are overcome by the present invention as will be explained below.